server-active-p

Arguments:
dde-info

Returns true if the Lisp process of the argument
dde-info is currently running as a DDE server,
and returns nil otherwise. This is true for
any process after the process has called open-server and before it later
calls either close-server or close-dde or it exits. Call
dde-info to
retrieve the dde-info object for a particular
Lisp process.

Compatibility note: Prior to release 6.1, this information was
contained in a global variable, but that design did not allow the DDE
facility to work in multiple processes other than Common Graphics
processes. So the variable was changed incompatibly to this function.
Any application that used the *server-active-p*
variable must change the reference to a call to server-active-p.